Waves of water flowing in the desert

02 August 2012 | Fact sheet

Lakes of Ounianga World Heritage Site, Chad

Background

The Lakes of Ounianga World Heritage Site consists of eighteen ecologically, geologically and hydrologically interconnected lakes within the Sahara Desert in the Ennedi region, West Ennedi department of Chad. The site consists of three distinct but contiguous parts, namely the four lakes of Ounianga Kebir, the fourteen lakes of Ounianga Serir, and the land surrounding the lakes. The main lakes of Ounianga Kebir and Ounianga Serir are approximately 40 km apart.

The Lakes of Ounianga are located in a basin situated some 50 to 80 m below a sandstone plateau. They are fed by fossil groundwater that flows from the foot of the sandstone cliff, compensating extremely high evaporation losses. The largest lake in Ounianga Serir, Lake Teli, covers a surface of 436 ha but is less than 10 m deep. It has a unique hydrological system, functioning as a giant evaporation pump which creates an underground water flow that feeds the other lakes of Ounianga Serir. Evaporation is markedly reduced in the other lakes of Ounianga Serir, which are mostly covered by floating reeds. This, in combination with the hydrological system of Ounianga Serir, is responsible for the formation of the largest freshwater lake ecosystem in a hyper arid area. On the other hand, the lakes of Ounianga Kebir, the largest of which is Lake Yoan with an area of 358 ha and a depth of 27 m, are hyper saline.

The protected areas system of Chad focuses on fauna and flora conservation, and contains the following categories: strict nature reserve, national park, wildlife reserve, game reserve, wildlife ranch, faunal management zone, zoological garden, and forest. None of these categories apply to the Lakes of Ounianga, which need protection rather for their hydrological operating system and aesthetic. The Lakes of Ounianga are protected through their designation as a “natural site” since 2010, and all activities that could threaten the integrity of the site, including mining, are prohibited. This designation is similar to IUCN Category III for protected areas.

View images of the World Heritage site

Size and location

The World Heritage Site covers a total surface area of 62,808 ha and is located in the western part of the Ennedi region, in the northeast of Chad, approximately 970 km from the capital of N’Djamena.

Flora and Fauna

The Ennedi area in general, and the Northern part of Erdi in particular, has not had a recent inventory of natural resources. Only a few mammals and birds have been identified, amongst which fox, hyena, jackal, fennec fox, cape hare and gazelle. The Ounianga region is home to waterfowl, such as Marbled Teal (Marmaronetta angustirostris, VU) and Cape Teal (Anas capensis), as well as passerine species. At Ounianga Serir, the freshwater lakes shelter several fish species, amphibians and invertebrates, but at Ounianga Kebir, the hyper saline lakes only support algae, microorganisms, and some also contain spirulina (Spirulina platensis), a cyanobacteria capable of fixing nitrogen through photosynthesis.

Threats

Although the populations of Ounianga Kebir and Ounianga Serir are small (about 9,000 and about 1,000 respectively), human impacts on the site are visible in a lack of waste management, and wastewater discharge is affecting the water quality of lakes Yoan and Teli, which are close to the two villages. However, environmental impact is limited.

Current levels of human activity such as subsistence fishing, therapeutic baths and salt extraction do not seem to threaten the site. Water extraction from the lakes for use by local communities is very limited and thus does not seem to result in a lowering of the groundwater level, but this needs to be carefully monitored. Any development project that requires a significant use of water resources will require a detailed environmental impact evaluation. In relation to the potential over-exploitation of water resources, the main threat is linked to potential development of intensive agriculture in the area. However, the Government of Chad has addressed this by a recently adopted Decree which aims to maintain traditional agricultural practices in the World Heritage Site instead of intensive agriculture.

Although relatively far from the border, Ounianga Kebir is a customs post where trucks must be unloaded for inspection and then reloaded. These operations take several days and the drivers and their passengers used to stay close to the lake. Nowadays, they are provided with bungalows further from the lake. Truck trafic to and from Libya is growing slowly in Ounianga Kebir, but it is likely that the environmental impact of this trafic has greatly diminished since 2006 when bungalows equipped with toilets were built in the town. Truck passengers arriving in Ounianga Kebir must stay in these bungalows. This strategy also seems to have reduced considerably the impact of tourists and passengers on Lake Yoan and its surroundings.

Development of tourism in the region is moderate. Two tour operators based in N’Djaména organize tours of Ounianga. Annually, 200 to 600 tourists visit the site in small groups. Tourists stay in mobile camps organized by tour operators. They leave all their waste at specially designated points within the site or take them back to N’Djaména. To maintain the site’s integrity, in agreement with administrative and traditional authorities, it has been decided that any future touristic facility or hotel must blend in with the local architectural features such as height, color, materials, shape of buildings, etc. Moreover, these facilities must meet eco-touristic and environmental principles and uses. A recently adopted Decree establishes the need to develop Environmental Impact Assessments for any new project, and will be a valuable tool to limit any environmental and social impacts associated with new proposed developments.